The SCTE (Society of Cable Telecommunications Engineers) has defined an addressable advertising system architecture that utilizes different information systems to assist in the selection of digital ad content for insertion into or presentation with program content. The advertising decision system (SCTE 130-3) identifies and coordinates the insertion of ads into media systems which may include linear TV advertising and video on demand, among other possibilities. Ads and program content can be classified and described in the content information system (SCTE-4). An ad decision system component (ADS) may register with a content CIS system to search for content and receive alerts when specific types of content are available. A placement opportunity information service (POIS) (SCTE 130-5) may be operated to identify when advertising inventory is available for use. The subscriber information service (SIS) (SCTE 130-6) may be operated to obtain information related to subscriber activities (preferences or viewing habits).